Carburetor



Dec. 13, 1927. 1,652,228

` L. ANGELINI CARBURETOR Filed March 11, 1924 Patented Dec. 13, i927.

UNITED STA'IES LUIGI ANGELINI,

or norm, ITALY.

caminamos.

Application filed March 11, 1924, Serial No. 698,559, and in Italy March 16, 1923.

rlhis invention relates to carburetors tor internal combustion engines in 'which one or more nozzles is or are used, and with or without a pilot nozzle.

It is known in connection with single nozzle carburetors to provide a rVenturi nozzle chamber which is surrounded by an annular space in communication with an automatically acting eXtra air supply valve, the extra air bein@ admitted within the Venturi chamber by a system of perforations and thus forming the necessary mixture with the fuel.

lt has also been proposed in a carburetor having a Venturi chamber within which the nozzle is arranged, to provide any annular space around the chamber, to which extra air may be admitted through an automatically acting air valve. The air supplied in this way is led into the mixing` chamber at the end oli the Venturi chamber through an annular opening, where it is deflected inwards by a conical. baffle which e'lrccts a mix'- ture of the air and 'fuel and causes eddies so as to facilitate the intimate mixture of the fluids.

i The invention `consists in an improved carburetor in which the air supply 'lior the jet is capable of being controlled by one ot two alternative devices according to the engine revolution speed, wherein 'for low speed the air is controlled by being passed through a primary calibrated opening immediately adjacent the jet, and at a higher engine revolution speed a correspondingly greater supply ot air is automatically admitted and controlled by a second and larger calibrated opening, the primary calibrated opening then functioning merely as an inlet.

The' invention will now be d escribed with reference to the accompanying drawings in which:

Fig. l is a vertical cross section of a vertical carburetor according to the invention.

Figs. 2 and A3 show a horizontal carburetor,

Fig. `2 being a horizontal cross section taken on line 2 2 ot Fig. 3, and

Fig. 3 a vertical section taken on line of Fig. 2. A

Referring to Fig. l, the carbureted mixture passes to the engine by way of the induction pipe l, from the two chambers 2 and 3. The carburetor connected to the engin-e by 'liange 4l. 5' and 6 are independent throttle valve, one 'for each et the chambers 2 and 3, while 7 and 8 'are the respective nozzles inthe chambers. 9 is the air admission opening tor bot-h chambers. The chambers are provided with a heating fluid chamber l2 through which may be circulated. bv means of the inlet l and the outlet ll,hot water or the exhaust products of combustion. The lower end of each chamber 2 and 3, is fitted with a Venturi tube 13, la respectively; and of these the tube 13 with its choke or air passage I is of ordinary construction, whilst the tube lei is of special construction, according to which it is transversely divided as shown in order to provide two spaced choke or air passages H and X respectively, which are both carefully calibrated. The passage H is circular and has centrally arranged therein the nozzle 8 whichreduces its total area, and is adapted to ali'ord passage to a quantity of air correctlyproportioned to the quantity of petrol discharged by the nozzle 8 at low engine revolution speed, while, when the Lengine is vrunning at high engine revolution speed, the passage X ot full circular area, is brought into action to supply to larger quantity ot air. F or this purpose, an air valve l is provided which is under the control of a very light coil spring l5, the valve chamber being in communication by passage 1G with an annular chamber 2l that surrounds the spaced portions of the choke passages X and H. rihe valve l5 is designed to open and admit air with a predetermined increase of engine revolution speed, thus admitting the necessary quantity oie air. It is to be noted that at low speed, the volume of air passing through the Venturi tube 14 will be ycontrolled by the calibrated passage H, `but on an increase of speed, the function ot air control will be transferred to the calibrated passage X, and then the passage H will function merely as an air inlet. In order yto afford a braking action on the engine when desired, the carburetor is litted towards its upper end, with a conical valve 17 for the admission oi additional air.

Referring to Figures 2 and 3, horizontal carburetor is shown, in which similar reference letters indicate like parts. In this case the two carburetor chambers 2 and 3 are reduced to a minimum and converge towards a port or passage formed in a rotary throttling plug 19 by which the engines revolution speed may be controlled. The nozzles Y and El are transversely arranged llO sil

within Athe tivo Venturi tubes 13 and lil, and iirstea'ijl` oli the lai-iger aassage X' ,being of conical torni, it is Acylindrical and' in communication by means ot duct 1G with'the 'air admitted through valve lzranchii'ii: trom the duct 1G an air passageway 2l, the end oli which is designed to be ctrfcred or uncovered by the rotairy plug' 41S) so as to come into 'action 'during the 'last le'w millimeters ot opening ot the Venturi nozzle chamber 13.

A pilot nozzle jfor slow `runninpl ogt 1known type'is' provided and so positioner'l 4that'the iassage vtor the `fuel. inii'ture to the induct'ion pipe cut o'li 1on opeiiiiig",t`,l'i mixture throttle valve in the .known niain'lei.'

` The 'said device comprises a hollow body 25 screwet'l 'into the carhiiiretor and has a transverse port 27 about midway of 'its length that connects bore with an outer concentric annular chamber 28. Such chainbei1 is' in. communication with a duct 29 in' the casing,` oit the throt le plugl valve 19. The latter is providedI with a duct "'ti' openingl .into the plug'. The 'nner end oit the duct is adz'tpted to retin 'y with the duct 29 when the' valve is turned ythat both of the Ven- 'tu'pri tubes are closed, but its outer end, as shown in Fig'. 3, is direct l downwards .so that it opens vinto the internalspace ot the plug; by means oit 'a small orifice 1 9. Vin the wall oit plugf 19 that communicates with the intake 1 when the' plug` 19 is closed, so that 'the 'engine will run light.

vThe lower 'end of the body 25 registers co-'a'Xially' with vthe nozzle 30 so that the fuel discharged therefrom mixes with air in the bore ogt the body 25 land passing:r successively through port 27, annular chamber 2 8` duct 29 and the duct- 86, and is admitted to the induction pipe.' By moving the body 25 more or less towards the nozle 30 placed` beneath it, a more or less rich mixture is formed.

In 'order to control the number ot revolutions 'of the engine, there is provided on the top oi.: body an adjustable screw 81 whichV by bein?,` screwed in, 'forms a partial closure oit the port 27 up to such' a point as to give passage to only a very small quantity olf mixture whereby the engine is reduced t0 veryk slow running.

From what has been stated above, it will be understood that when the ,throttle plug valve 19 is opened for effective normal running of the engine under load, the duct 29 will no longer be in register with'the duct 23,6, so that the above described slow runningjet is put 'completely out of action. Vllhefoperation oit'the carburetor is as follows:

Assumingl that the throttle valve (5 is open and 'that the engine is running; at slow speed, the 'cai?ln'1i"etor 'chamber 2 is brought into fiction, The suction of the engine will now cause `a V[low of air through the annular calibrated choke passa 55e ll t'lraufing siiliicientfuel' through the nozzle '8' to malte a correct mixture. Should the engine speed increase 'then "the iiiiii't'ure will be Ytound loo rich as the calibrated passage H cannot pass sul# 'hcie'nt air. (')Wiuel to the tension then brought about in the kchalynber 2, the valve 1'5 'opens automatically a'n'd'adinits an auxiliary supply ot air to the annular clianiber 2.1 surroundin'g` .the Venturi chamber' 1d, such eXtra air flowing `through' the' calibrated choke passage X ot larger arca'than that ot H Wherelliy a `correct n'iix'tiiire tor the higher engine speed is obtained. Thus the 'function of air contriil is' tran'sterred ,trom the annular passage H.' to ithe .larger opening 'X and maintains ,the right mixture.'

It' is to Aunvderstoed that should still higher engine speed be required, then `the extra carburetor chamber 2 may be brought into action. it such is needed Thus ltl'ic `carhuretor may be used with lonly the single chaniber 2 with or without ya pilot nozzle, or it may be supplementec'l by the chaniber.

ln Figure 1 shrnvjng the veftjcal carburetor` ,the throttle passage H and are combiued in 4one blootY i ert'ed into `thc nar-- buretor body, the said block having'lateral holes soy that the interior v(and consequently passage may communicate With chamber 21. and 'thereupon with valve through passage 16.

ln Figures 2 and 3 showing' a horizontal iarburetor, owingto the different arrange ment Iof the members comprising,r the carburetor, the throttle passage-s H and X are not combined into'a single block but 'H is 4fitted separately. They also could be made boringr suitable holes in the carburetor body.

lVoiking' is identical, in b oth types, Qthere being' lirottle passages H lwith the vfurl nozzle in the center in both. The passage X provided, which in both types conjiinunicates in the same manner with atmosphere through and by chamber 21, passage 1,(3 and valve 15.

Pzssage 2i, 2, conies into operation when the mixture throttle valve is it'ully open and mixture is being supplied tlnongh Venturi nozzle chamber 13. Passage 24s is iter the purpose et maintaining' 'the suction on the valve 15 so that it. remains open, and therefore the working;r of the carburetor constant.

Having now particularly described my said invention, what I claim is:

In a carburetor, in combination, a body ha ving an Hi'iduction tube therein and two air inlets at van angle to each other and to'said tube,` a rotatable member having' a. pzltssage therethrough aiflupted to connect: one or both inlets to said tube, a choke in each inlet. a ituel nozzle in. each choke, av second choke l Ol) bei' being,l adapted to close said last inentioned passage when the single air inlet having two chokes is in use and to open the same when both air inlets are in use.

In testimony Where-of I have hereunto signed my name.

LUIGI ANGELINI. 

